Analysis and Design of Radiation-Hard Silicon Photonics Integrated Circuits for High-Speed Data Transmission in High Energy Physics Applications

Silicon Photonics (SiPh) has become a viable technology for reducing the size, weight and energy consumption of optical devices for short-reach optical interconnects. Because of its CMOS compatibility, SiPh can leverage the maturity of technological processes of the microelectronic industry and provide an high-yield and accurate fabrication, enabling low-cost and high-volume production. All-silicon modulators are an essential component of optical communication links and significant research was dedicated in developing devices with a large bandwidth, low insertion losses and low drive-voltages. SiPh is currently being evaluated at the Europen Organization for Nuclear Physics (CERN) in order to assess its suitability for use in high energy physics (HEP) experiments. Optical and electronic components installed in the particle detection region have to ensure high reliability to radiation exposure. Since silicon is already established as a very good material from the radiation hardness point of view, SiPh is expected to provide a valid opportunity for the design of next generation optical links. In the framework of a joint research activity between Dipartimento di Ingegneria dell’Informazione (DII), Scuola Superiore Sant’Anna (SSSA) and Istituto Nazionale di Fisica Nucleare (INFN) and given the author’s research experience in the CERN’s optoelectronics group, this thesis is centered on the design of a novel high-speed optical modulator with improved resistance against total ionizing dose (TID) exploiting ISIPP50G fabrication technology (available throught Europractice). An optimization of design parameters, such as slab thicknesses, doping placements and electrodes layout, has been carried out to improve both device radiation hardness and speed performances. A prototype of the high-speed radiation-hard MZM designed within this activity is scheduled to be taped out on the upcoming ISIPP50G multi-project wafer (MPW) run